create table employee(
emp_id int,
emp_name varchar(10),
emp_salary int,
manager_id int
);

insert into employee values(10, 'Anil', 50000, 18);
insert into employee values(11, 'vikas', 75000, 16);
insert into employee values(12, 'nisha', 40000, 18);
insert into employee values(13, 'nidhi', 60000, 17);
insert into employee values(14, 'payal', 80000, 18);
insert into employee values(15, 'mohit', 45000, 18);
insert into employee values(16, 'rajesh', 90000, null);
insert into employee values(17, 'raman', 55000, 16);
insert into employee values(18, 'santosh', 65000, 17);

select * from employee;
select b.emp_id, b.emp_name, avg(a.emp_salary) from employee a, employee b where a.manager_id=b.emp_id group by b.emp_id, b.emp_name order by b.emp_id;

drop table employee;
rollback;
select * from employee;